Ultrasound-equipped colonoscope for point-of-procedure colorectal preparation and examination

Colorectal cancer is the second leading cancer killer in the United States. Poor colon preparation occurs in 20–40% of colonoscopies in the community, which increases the duration of the colonoscopy by at least 10% and the cost of the procedure by up to 22% due to repeat visits. The goal of this research was to develop and preliminarily evaluate the first ultrasound-cavitation equipped colonoscope as an innovative approach to liquefy fecal matter with water/cavitation and improve colonoscope utility. Two ultrasound-equipped colonoscopes were developed. The first consisted of a 30 element 235 kHz array that was mounted as a cap on the tip of a commercial colonoscope (Olympus). The second consisted of a Time-Reversal Acoustic extroporeal 32 channel 100 kHz array that was electrically steered to the commercial colonoscope using PVDF detectors to acquire and monitor the TRA focusing routines. Both systems were evaluated in a series of bench tests for fecal liquification, as well as in the porcine cadaver. Results show that ultrasound exposure assists the liquification of fecal matter and 50 kPa exposure to ultrasound increases liquification by greater than 50 times. Blinded histological reports on excised tissues showed no significant different findings between control and ultrasound experiments.